The invention relates to an automatic pedal for a bicycle, in particular for an all-terrain bicycle (ATB), but which could also be used on a touring bicycle.
This automatic pedal is, but not exclusively, a pedal with double retention surface of the type described in French patent application FR 99 00722 of the applicant.
The pedal comprises a pedal body provided with a transverse recess for the securement to the body an axle connected to a pedal crank of the bicycle. This axle is conventionally mounted in a bearing disposed in the pedal body and permits rotation of the pedal about the axle during pedaling.
The pedal body is provided with a front engagement member, a hooking element for a plate fixed below the sole of a bicycle shoe, and with a rear movable retaining member for this plate. This rear member is pre-stressed by resilient means which usually is constituted by at least one spring which can be of the coil compression type, torsion type, tension type or blade type. The pedal often comprises moreover a cam or screw device permitting adjustment of the tension of the resilient means.
In a pedal of this type, the assembly constituted by the rear movable retaining member, the resilient member urging this member toward its retaining position, and the device for adjusting the tension of the spring, comprises in effect a relatively high number of elements, which requires substantial time during assembly on the body of the pedal. Moreover, it is also necessary to provide recesses within the pedal body to receive all these elements, which complicates production.
The object of the invention is to provide an automatic pedal that is extremely simple and less difficult to produce because it comprises a minimum number of elements, in particular as to the rear movable member. As a result, the assembly of the pedal is simplified and the cost of the pedal is greatly reduced.
Another object of the invention is to provide a device for the rapid and simple adjustment of the hardness of the resilient return means for the movable rear member.
The invention has for its object an automatic bicycle pedal of the type comprising a pedal body provided with a front fixed member for engagement with a hooking member fixed below the sole of the shoe of the bicyclist, and the rear movable retaining member for said hooking member, characterized in that the rear retaining member comprises a resilient member fixed in containing relationship on the pedal body and operating bendingly between a bent position for freeing the hooking member and a retaining member of this latter against a retaining surface on the pedal body.
According to other characteristics of the invention:
the resilient member comprises a blade operating by bending along its width;
the blade is clamped against the pedal body with the help of a plate disposed outside the blade and which defines the line of bending of the blade;
the plate comprises a recess opening at the upper end of the plate and defining a bending space for the blade between the body of the pedal and the plate, the upper edge of the recess limiting the bending of the blade, whilst its lower edge defines said bending line;
the plate is adjustable in height so as to displace the line of bending of the blade to adjust the hardness of the blade by modifying the length of the lever arm of the latter;
the plate is, so as to permit its height adjustment, provided with an oblong opening through which passes a securement screw of the blade onto the pedal body, by gripping the blade between the pedal body and the plate;
the resilient element is overall of C shape and constitutes simultaneously a front fixed member for engagement with the retaining element on a pedal with a double retention plane;
the plate and the pedal body comprise indexing means indicating an increase or decrease of the hardness of the blade;
the blade comprises in its median portion a U-shaped cutout which delimits a tongue in which is provided a securement hole for the blade such that the length of the lever arm of the portion of the blade subjected to deformation will be increased;
the blade comprises in its median portion an elongated slot, such that the blade deforms uniformly, in this portion it is flattened and beveled;
the blade comprises in its median portion a triangular opening, the lower part of the blade adjacent the hole 11 for passage of the screw being more stressed than the upper portion;
the blade comprises in its median portion two opposite and symmetrical cutouts which narrow the blade upwardly;
the blade in its median portion comprises two opposite and symmetrical cutouts which extend parallel to each other;